Of 5 endometrial cell lines (RL95, KLE, HEC-1B, HEC-1A, Ishikawa and an ovarian endometrioid carcinoma cell line (OEA) (TOV112D)), HEC-1A, HEC-1B, Ishikawa and TOV112D which have previously showed high Wnt/β-catenin signaling activity [22, 25] expressed lower Sox7 but higher levels of CyclinD1, C-myc and FGF9 (Fig. 1B) Taken together, these findings suggest that Sox7 may be a negative regulator of Wnt/β-catenin signaling activity and is frequently down-regulated in endometrial cancer. The gene discussed is FGF9; the disease is endometrial cancer.